Agentic Biomes — Quick Start Guide

A text walkthrough for a level with one terrain, one Terraformer, and one or more biomes.

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Step 1: Install and Enable the Plugin

From Fab: Install Agentic Biomes for Unreal Engine 5.8. A project-local installation lives in YourProject/Plugins/AgenticBiomes/.

In Edit → Plugins, enable Agentic Biomes (category Procedural). Its descriptor pulls in PCG, PCGBiomeCore, Niagara, PCGGeometryScriptInterop, and ToolsetRegistry.

For a MeshTerrain terrain, also enable MeshPartition, PCGMeshPartitionInterop, PCGPrimitives_MeshPartitionInterop, and MeshTerrainMode. Restart the editor when prompted.

The plugin's sample meshes, runtime templates, and terrain surface textures ship with it; no other pack is needed.

Step 2: See It Working First

In the Content Browser's settings, enable Show Plugin Content, then open one of the four showcase levels under Plugins → Agentic Biomes Content → Maps → Showcase:

Select the Terraformer actor in the Outliner. In its Details panel press Build Biome Volumes on a volume level or Build Biome Map on a texture level. Trees, rocks, and props generate into the level; ground cover such as grass, ferns, and stones is generated on the GPU around the camera at runtime.

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Step 3: Add a Terraformer to Your Own Level

1. Add terrain: a Landscape, or a MeshTerrain.
2. Place a Terraformer (AAgenticTerraformer) from the Place Actors panel.
3. Leave Terrain Backend on Auto. The Terraformer scans the level and reads Resolved Terrain Backend back to you. A level with both backends, or with neither, is a hard error: set Terrain Backend to Landscape or MeshTerrain explicitly when the level holds both.
4. Make sure the biomes you want exist as assets. See Biome Assets.

Step 4: Choose a Placement Mode

Set Placement Mode on the Terraformer, then follow one route. Each is described in full in Placement.

Painted biome map

Set PlacementMode to BiomeMap.

1. Assign a colour texture to Biome Map.
2. List your biomes in Biome Map Biomes. This array is the palette: each biome's definition colour claims the matching texels.
3. Press Validate Biome Palette. It reports duplicate or too-close colours, a missing definition, a clash with the reserved "no biome" black, and biomes with no content.
4. Press Build Biome Map.

No texture yet? Bake Banded Biome Map writes a starter map with one horizontal band per palette entry that you can paint over. Audit Biome Map counts how many texels each colour claims.

Sector grid

Set PlacementMode to Grid: press Auto Grid to spawn the sectors, assign biomes per sector, then press Build All.

Box volumes

Biome Map Biomes is editable only while Placement Mode is not Grid, so set it to BiomeMap or Hybrid first. List your biomes in Biome Map Biomes and press Build Biome Volumes. It places one box region per biome that has content, tiling the terrain in a near-square grid; no texture is needed. You can select a region in the Outliner and move or scale it, but the next build re-tiles from scratch and discards hand edits.

Closed spline

Add an Agentic Biome Region, set Shape to Spline, assign the biome, shape the spline as a closed loop, then press Build Spline Biomes on the Terraformer.

Both grid and map

Hybrid keeps the sector grid running while painted biomes come from the map.

Step 5: Verify the Result

Press Verify Biome Map Regions. It reports PASS or FAIL for what was actually generated: every region produced a non-empty cache, and no two regions claim the same cell. Run it after the build has finished generating.

If nothing generates, open the Output Log and filter for LogAgenticBiomes; the plugin names the reason there, for example a level that contains no terrain. See Troubleshooting.

Step 6: Set the Terrain Surface

Nothing in the plugin assigns the terrain material for you. On a Landscape, set Landscape Material to MI_AT_LayerStack_Landscape and paint its Dirt, Gravel, and Sand layers. On a MeshTerrain, set the Material of your Mesh Partition definition to MI_AT_LayerStack_MeshTerrain. See Terrain Material for the layer stack, the painted-biome instance, and the Runtime Virtual Texture and Nanite switches.

Step 7: Save and Extend

Save the level and your biome assets. Reopen the map and confirm the regions and generated content are still there. Duplicate a shipped biome into your own project content before editing it, so an update does not overwrite your work.

Extend in order: biome assets first, then placement, then runtime ground cover, then roads and exclusions, then the wind bridge. Rebuild and verify after each addition.

Next Steps

• Biome Assets — Author species rows and runtime entries
• Placement — Every placement route in detail
• Runtime Ground Cover — GPU ground cover around the camera
• Agent Toolsets — Drive the same workflow from an MCP client with 28 editor tools, including BuildLevelAs for a level's first build
• Troubleshooting — Diagnose setup problems first